Atmospheric air is a mixture of dried air, and steam water and is called humid air. This mixture of gases is the one that is conditioned in ambient control systems by means of humidifiers, and conditioned air units. From now on, the word “air” will be used to denote the mixture of dried air, and water vapor as naturally occurring in the atmosphere.
According to standard 55-1981 from ANSI/ASHRAE (American National Institute of Standards/American Society of Heating, Refrigeration and Air Conditioning Engineers) a series of ideal conditions for comfortable indoor environments were set forth. According to this standard, humidity is a determinant factor for human comfort. At temperatures between 20° C. and 26° C. an indoor environment is comfortable as long as the air humidity is between 30 and 70%.
From the above, there is a need for humidifiers as co-adjuvants of human comfort.
In the state of the art, a diverse kind of humidifiers is known; humidifiers are classified according to their functions. Such classification consists of:
Evaporative humidifiers: In such systems, a fan makes air circulate through a moisturized material. Water contained in the material is transferred to the air stream, thereby increasing the relative humidity of the air stream.
Liquids have a physicochemical property called vapor pressure. Such property determines the balance between the vapor phase, and the liquid phase of a liquid. By virtue of such property, a liquid will always tend to establish a balance between the liquid and vapor phases.
The evaporation phenomenon takes place when vapor is generated as a result of the balance between the liquid-vapor phases. If a gas stream absorbs vapor at balance with the liquid phase, fresh vapor will be generated to re-establish the liquid-vapor balance.
In the evaporative humidifiers, an air stream takes up the vapor that is balanced with the liquid phase, the balance is broken, and new vapor is generated to re-establish the balance. The air that comes out of the humidifier is humid air.
The evaporative humidifiers have the disadvantage that the moisturized material can become a source for the growth of fungus, algae, and aerobic germs.
U.S. Pat. No. 4,844,842 published on the 4th of Jul., 1989 describes an apparatus of this sort. According to such patent, the moisturizing element being formed as a rotatable disc. The bottom of the disc is submerged in a water bath or in an aqueous liquid while the top is in contact with an air stream. When such disc rotates, the top is submerged in the liquid while the submerged part emerges already wet, and gets in contact with the air stream.
U.S. Pat. No. 5,945,038 describes an evaporative humidifier that consists of an absorbent material where a portion of the humidification material is submerged, and the upper portion is exposed to air, in such patent the use of a floater to control the water supply is also described.
Boiling Humidifiers. In such evaporators, an air stream is mixed with a steam stream that was obtained from boiling water.
Such evaporators have the advantage of eliminating all kinds of microorganisms; however, they generate a “white dust” that consists of insoluble salts and minerals contained in water that are entrained along with the steam streams. On the other hand, boiling humidifiers have the disadvantage of using a great deal of energy to boil water. On the other hand, such humidifiers do not provide the means to remove those pollutants already present in the air stream.
Warm Mist Humidifiers. These humidifiers operate with water vapor near the dew point temperature. Water vapor is cooled just before contacting the air stream, in such a way that a gaseous mixture of steam water and small droplets of water, and air is obtained.
Such units have the disadvantage of keeping air pollutants. Besides, such humidifiers do not provide means to remove pollutants present in the air stream either.
Cold Mist Humidifiers. In these humidifiers, water or an aqueous liquid is sprayed, and then mixed with the air. Such equipment has the disadvantage of keeping the pollutants, and microorganisms in the humid air stream.
Such humidifiers do not provide the means to remove those pollutants present in the air stream either.
Ultrasonic humidifiers. These humidifiers use high frequency vibrations to spray, and evaporate water.
The ultrasonic evaporators have the disadvantage of requiring very costly maintenance. Besides, these humidifiers do not provide the means to remove the pollutants present in the air stream either.
As above mentioned, the boiling humidifiers, the warm mist humidifiers, the cold mist humidifiers, and the ultrasonic humidifiers do not remove those pollutants present in the air streams so that in such humidifiers, the pollutants are entrained along with the humidified air stream.
On the other hand, in the case of evaporative vaporizers, still when the dust is removed by filtering the moisturized material, such dust that is in contact with the moisturized material promotes the growth of fungus, algae, and aerobic germs. Besides, as times passes by, the accumulated dust in the moisturized material tends to obstruct the air circulation through the moisturized material, and then affects water transfer to the steam stream.
To remove dust, different kinds of filters are known. Also, it is known the use of foam to control dust in mining environments, for instance, in carbon mines. The foam is generated by means of ejectors where an air stream is mixed with a water stream at high speeds.
U.S. Pat. Nos. 4,000,992, and 4,400,220 of Jan. 4th, 1977, and Aug. 23rd, 1983, describe a system for dust removal by bubbles into a cyclone.
Therefore, in the state of the art, there is no evaporator that also removes dust, and pollutants from the humidified air stream without generating fungus, algae, and aerobic germs.
For this reason, an object of the invention is to provide a system and an apparatus to transfer liquid molecules by evaporation to a gas stream in contact with the liquid.
For this reason, an object of the invention is to provide a humidifier system and an apparatus capable of eliminating air pollutants.
Another object of the invention is to provide a humidifier system, and an apparatus capable of eliminating dust and microorganisms from the air stream.
One more object of the invention is to provide a system of easy maintenance capable of efficiently humidifying, removing air particles, disinfecting, and providing aroma to the air.